BMAL1 and colorectal cancer: Consistently, Zeng et al. reported that BMAL1, a transcriptional activator of PER2, increased oxaliplatin sensitivity of colorectal cancer.21 Taken together, our results revealed that PER2 has significantly synergistic effects on the cytotoxicity with oxaliplatin and a positive correlation exists between PER2 expression pattern and oxaliplatin efficacy.